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Vascular Plants of California
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Leersia oryzoides

Higher Taxonomy
Family: Poaceae (Gramineae)View DescriptionDichotomous Key
Habit: Annual to woody perennial herb; roots generally fibrous. Stem: generally round, hollow; nodes swollen, solid. Leaf: alternate, 2-ranked, generally linear, parallel-veined; sheath generally open; ligule membranous or hairy, at blade base. Inflorescence: various (of generally many spikelets). Spikelet: glumes generally 2; florets (lemma, palea, flower) 1--many; lemma generally membranous, sometimes glume-like; palea generally +- transparent, +- enclosed by lemma. Flower: generally bisexual, minute; perianth vestigial; stamens generally 3; stigmas generally 2, generally plumose. Fruit: grain, sometimes achene- or utricle-like.
Genera In Family: 650--900 genera; +- 10550 species: worldwide; greatest economic importance of any family (wheat, rice, maize, millet, sorghum, sugar cane, forage crops, ornamental, weeds; thatching, weaving, building materials). Note: Generally wind-pollinated. Achnatherum, Ampelodesmos, Hesperostipa, Nassella, Piptatherum, Piptochaetium, Ptilagrostis moved to Stipa; Elytrigia, Leymus, Pascopyrum, Pseudoroegneria, Taeniatherum to Elymus; Hierochloe to Anthoxanthum; Lolium, Vulpia to Festuca; Lycurus to Muhlenbergia; Monanthochloe to Distichlis; Pleuraphis to Hilaria; Rhynchelytrum to Melinis. The following taxa (in genera not included here), recorded in California from historical collections or reported in literature, are extirpated, lacking vouchers, or not considered naturalized: Acrachne racemosa (Roth) Ohwi, Allolepis texana (Vasey) Soderstr. & H.F. Decker, Amphibromus nervosus (Hook. f.) Baill., Axonopus affinis Chase, Axonopus fissifolius (Raddi) Kuhlm., Coix lacryma-jobi L., Cutandia memphitica (Spreng.) K. Richt., Dinebra retroflexa (Vahl) Panz., Eremochloa ciliaris (L.) Merr., Eustachys distichophylla (Lag.) Nees, Gaudinia fragilis (L.) P. Beauv., Miscanthus sinensis Andersson, Neyraudia arundinacea (L.) Henrard, Phyllostachys aurea Rivière & C. Rivière, Phyllostachys bambusoides Siebold & Zuccarini, Rottboellia cochinchinensis (Lour.) Clayton, Schedonnardus paniculatus (Nutt.) Branner & Coville, Schizachyrium cirratum (Hack.) Wooton & Standl., Schizachyrium scoparium (Michx.) Nash, Themeda quadrivalvis (L.) Kuntze, Thysanolaena latifolia (Hornem.) Honda, Tribolium obliterum (Hemsl.) Renvoize, Zea mays L., Zizania palustris L. var. interior (Fassett) Dore, Zoysia japonica Steud. Paspalum pubiflorum E. Fourn., Paspalum quadrifarium Lam., are now reported for southern California (J Bot Res Inst Texas 4:761--770). See Glossary p. 30 for illustrations of general family characteristics.
eFlora Treatment Author: James P. Smith, Jr., except as noted
Scientific Editor: James P. Smith, Jr., J. Travis Columbus, Dieter H. Wilken.
Genus: LeersiaView Description 

Common Name: CUTGRASS
Habit: Perennial herb from long rhizomes. Stem: generally 1, decumbent to erect. Leaf: cauline; ligule membranous; blade flat to folded. Inflorescence: panicle-like, open; lateral branchlets, spikelet stalks arched to wavy. Spikelet: laterally compressed; glumes 0; floret 1, bisexual, falling as 1 unit; lemma, palea firmly membranous; lemma strigose on back, awnless, 5-veined; palea +- = lemma.
Species In Genus: 17 species: tropics, warm temperate America, Eurasia. Etymology: (J.D. Leers, German botanist, 1727--1774)
eFlora Treatment Author: Dieter H. Wilken
Reference: Pyrah 2007 FNANM 24:42--45
Unabridged Reference: Pyrah 1969 Iowa State J Sci 44:215--270
Leersia oryzoides (L.) Sw.
Stem: 1--1.5 m; nodes short, soft-hairy. Leaf: sheath glabrous to minutely scabrous; ligule +- 1 mm, truncate; blade 10--28 cm, 8--14 mm wide, margin strongly scabrous, with downward-pointing teeth. Inflorescence: 12--20 cm; lower branches +- spreading. Spikelet: 4--5 mm, oblong to narrowly elliptic; lemma 4--5 mm, width 3--5 × palea width. Chromosomes: 2n=48.
Ecology: Marshes, streams, ponds; Elevation: < 1200 m. Bioregional Distribution: CA-FP (exc SCoR); Distribution Outside California: to British Columbia, eastern North America; Eurasia. Flowering Time: Aug--Oct Note: Lateral inflorescences enclosed by sheath, generally cleistogamous. Leersia hexandra Sw., with ascending to appressed inflorescence branches, smaller spikelets, has been reported, but not documented, in rice fields in ScV.
Jepson eFlora Author: Dieter H. Wilken
Reference: Pyrah 2007 FNANM 24:42--45
Index of California Plant Names (ICPN; linked via the Jepson Online Interchange)

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Botanical illustration including Leersia oryzoides

botanical illustration including Leersia oryzoides


Citation for this treatment: Dieter H. Wilken 2012, Leersia oryzoides, in Jepson Flora Project (eds.) Jepson eFlora,, accessed on June 19, 2021.

Citation for the whole project: Jepson Flora Project (eds.) 2021, Jepson eFlora,, accessed on June 19, 2021.

Leersia oryzoides
click for enlargement
© 2008 Keir Morse
Leersia oryzoides
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© 2016 Keir Morse
Leersia oryzoides
click for enlargement
© 2008 Keir Morse
Leersia oryzoides
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© 2011 Steve Matson
Leersia oryzoides
click for enlargement
© 2011 Steve Matson
Leersia oryzoides
click for enlargement
© 2008 Keir Morse

More photos of Leersia oryzoides in CalPhotos

Geographic subdivisions for Leersia oryzoides:
CA-FP (exc SCoR)
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map of distribution 1
(Note: any qualifiers in the taxon distribution description, such as 'northern', 'southern', 'adjacent' etc., are not reflected in the map above, and in some cases indication of a taxon in a subdivision is based on a single collection or author-verified occurence).


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Data provided by the participants of the  Consortium of California Herbaria.
View all CCH records
All markers link to CCH specimen records. The original determination is shown in the popup window.
Blue markers indicate specimens that map to one of the expected Jepson geographic subdivisions (see left map). Purple markers indicate specimens collected from a garden, greenhouse, or other non-wild location.
Yellow markers indicate records that may provide evidence for eFlora range revision or may have georeferencing or identification issues.

CCH collections by month

Duplicates counted once; synonyms included.
Species do not include records of infraspecific taxa, if there are more than 1 infraspecific taxon in CA.
Blue line denotes eFlora flowering time (fruiting time in some monocot genera).